Impact of Minimum Wages on Employment: Evidence from China

This article examines the impact of the minimum wage on employment in China using data from 2000 to 2005. The effect of the minimum wage on employment levels was found to be mixed. Overall, minimum wages have no significantly adverse effect on employment. In particular, the results in the eastern region of China indicate few significant negative effects, which is consistent with the minimum wage theory in the competitive market. In contrast, the central and western regions experience few significantly positive effects, which is consistent with the theory in the monopsony model. The results are robust regardless of ownership (non-state-owned enterprises, collectives, private enterprises, and other types), industry type (manufacturing, wholesale and retail trade, hotel and restaurant), and gender of workers. Low real minimum wages, weak enforcement capabilities, and the buyer\u27s labor market—the three factors that may account for the effects of minimum wages on employment in China—are analyzed

ATF4 Contributes to Ovulation via Regulating COX2/PGE2 Expression: A Potential Role of ATF4 in PCOS

Ovulatory disorder is common in patients with hyperprolactinemia or polycystic ovary syndrome (PCOS). Previous studies have shown that ATF4 plays critical role in apoptosis and glucose homeostasis, but its role in regulating reproductive function was not explored. The present study investigated the role of ATF4 in ovarian ovulatory function. Human granulosa cells (hGCs) from 48 women newly diagnosed with PCOS and 37 controls were used to determine ATF4 expression. In vitro cultured hGCs were used to detect the upstream and downstream genes of ATF4. A shRNA- Atf4 lentiviral vector (shAtf4) was injected into rat ovaries to establish an in vivo gene knockdown model to further assess the in vivo relevance of the results from PCOS women. We found that ATF4 expression was lower in hGCs from PCOS patients than in hGCs from non-PCOS women. Many pivotal transcripts involved in cumulus-oocyte complex (COC) expansion, extracellular matrix (ECM) remodeling, and progesterone production were significantly down-regulated after ATF4 knockdown. ChIP-qPCR assays indicated that ATF4 could directly bind to the COX2 promoter and that ATF4 knockdown could attenuate human chorionic gonadotropin (hCG)-induced COX2 expression and PGE2 production. The in vivo study showed that shRNA-lentivirus mediated Atf4 knockdown in rat ovaries led to reduced number of retrieved oocytes. Collectively, these findings suggested previously unknown roles of ATF4 in ovulation. Furthermore, ATF4 malfunction in PCOS patients may impact the ovulation process, which could contribute, in part, to the pathogenesis of PCOS

Application of a Diatom Transfer Function to Quantitative Paleoclimatic Reconstruction — A Case Study of Yunlong Lake, Southwest China

Although diatom records from lake sediments have been used for quantitative paleoclimatic reconstruction, their validity and sensitivity have rarely been tested rigorously. At Yunlong Lake, an alpine lake in Southwest China, we studied the seasonal succession of diatom assemblages to produce a mean surface water temperature (MSWT) transfer function. In addition, based on the spatial distribution of surface diatom assemblages with water depth, we produced a diatom-water depth (WD) transfer function. Combined with the analysis of diatom assemblages in a sediment core (YL2013-A), changes in surface water temperature and water level over the last ∼100 years were quantitatively reconstructed using the diatom-based transfer functions. Comparison with records of regional meteorology and reservoir water capacity revealed that the diatom-based lake water level reconstruction is a sensitive indicator of short-term fluctuations in precipitation, and it also reflects a long-term stepwise rise in water level caused by the impounding and large-scale extension of the reservoir. In addition, the diatom-inferred MSWT is consistent with the changes in air temperature prior to large-scale human disturbance of the site. However, after the extension of the reservoir, although the regional air temperature continued to increase, the water temperature decreased substantially. This suggests that the large increase in lake water volume in the short term led to a decrease in the average water temperature, which in turn led to the occurrence of a diatom bloom in the cold season. The results demonstrate that diatom transfer functions based on modern observations of the same lake has a high environmental sensitivity and can be used for the quantitative reconstruction of regional climate change. Overall, our findings provide a foundation for the use of lake diatom records for quantitative paleoclimatic reconstruction on various timescales

Screening of deafness-causing DNA variants that are common in patients of European ancestry using a microarray-based approach

The unparalleled heterogeneity in genetic causes of hearing loss along with remarkable differences in prevalence of causative variants among ethnic groups makes single gene tests technically inefficient. Although hundreds of genes have been reported to be associated with nonsyndromic hearing loss (NSHL), GJB2, GJB6, SLC26A4, and mitochondrial (mt) MT-RNR1 and MTTS are the major contributors. In order to provide a faster, more comprehensive and cost effective assay, we constructed a DNA fluidic array, CapitalBioMiamiOtoArray, for the detection of sequence variants in five genes that are common in most populations of European descent. They consist of c.35delG, p.W44C, p.L90P, c.167delT (GJB2); 309kb deletion (GJB6); p.L236P, p.T416P (SLC26A4); and m.1555A>G, m.7444G>A (mtDNA). We have validated our hearing loss array by analyzing a total of 160 DNAs samples. Our results show 100% concordance between the fluidic array biochip-based approach and the established Sanger sequencing method, thus proving its robustness and reliability at a relatively low cost

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Professional Task-Based Curriculum Development for Distance Education Practitioners at Master’s Level: A Design-Based Research

Curriculum development for distance education (DE) practitioners is more and more focusing on practical requirements and competence development. Delphi and DACUM methods have been used at some universities. However, in the competency-based development area, these methods have been taken over by professional-task-based development in the last decade, which has not been applied in the open and distance education area so far. Is the professional-task-based curriculum development approach suitable for open and distance education? This study aims to develop a Master Degree curriculum for DE practitioners in China based on professional tasks. Design-based research (DBR) was used and two cycles of DBR were conducted. Interviews and observations were used to collect data. In the first round of DBR, the authors find that professional-task-based development is feasible and could direct more closely to practical requirements of competencies, and that meanwhile, this approach has some disadvantages and limitations. In the second round of DBR, the approach was revised and results showed that the revised approach was much more suitable and reasonable for DE practitioners. Results of this study include: 1) professional-task based curricula for DE practitioners in China; 2) a curriculum development approach for open and distance education revised from professional-task-based development

Impact of Minimum Wages on Employment

This article examines the impact of the minimum wage on employment in China using data from 2000 to 2005. The effect of the minimum wage on employment levels was found to be mixed. Overall, minimum wages have no significantly adverse effect on employment. In particular, the results in the eastern region of China indicate few significant negative effects, which is consistent with the minimum wage theory in the competitive market. In contrast, the central and western regions experience few significantly positive effects, which is consistent with the theory in the monopsony model. The results are robust regardless of ownership (non-state-owned enterprises, collectives, private enterprises, and other types), industry type (manufacturing, wholesale and retail trade, hotel and restaurant), and gender of workers. Low real minimum wages, weak enforcement capabilities, and the buyer's labor marketâthe three factors that may account for the effects of minimum wages on employment in Chinaâare analyzed.

Rapid Construction of the ABC Ring System in the <i>Daphniphyllum</i> Alkaloid Daphniyunnine C

An efficient and scalable synthesis of the ABC ring system common to the calyciphylline A-type alkaloids has been developed. The tricyclic core of the alkaloids features a bowl-shaped [6–6–5] skeleton with five stereogenic centers including an all-carbon quaternary center. It was constructed rapidly from a readily available carvone derivative through a seven-step sequence involving an aza-Michael addition and Pd-catalyzed enolate α-vinylation as key steps

Evaluation of the Inflammatory Response in Macrophages Stimulated with Exosomes Secreted by Mycobacterium avium-Infected Macrophages

Exosomes secreted from Mycobacterium avium-infected macrophages contain numerous antigens of both M. avium and the host cell and are involved in the induction and expression of the inflammatory responses in macrophages. The interaction between exosomes secreted from M. avium-infected macrophages and macrophage phagocytosis, cytokine secretion, immunostimulation, and apoptosis was analyzed. Upon stimulation with exosomes secreted from M. avium-infected macrophages, the phagocytosis of dextran by treated macrophages was increased. Furthermore, the expression of CD40, CD80, CD81, CD86, HLA-DR, and most notably CD195 was enhanced. Additionally, the secretion of IL-6, IL-8, IL-10, IFN-γ, and TNF-α was increased by stimulated macrophages. Exosome stimulation did not induce macrophage apoptosis when compared with macrophages infected with M. avium. Caspase expression, including that of caspases 3, 6, and 8, was also not altered in exosome stimulated macrophages. Thus exosomes trigger the inflammatory response in macrophages owing to the presence of bacterial antigens but have no effect on macrophage viability